YOKOSUKA NAVAL BASE, Japan — The USS Nimitz Carrier Strike Group became the third carrier group operating in the Pacific when it sailed into the region on Wednesday.

The 3rd Fleet’s Nimitz group, which includes Carrier Air Wing 11 and Destroyer Squadron 9, recently wrapped up operations in the Middle East, where it has been attacking Islamic State targets as part of Operation Inherent Resolve.

The group will make a port visit to an unspecified location before heading to their homeport of Bremerton, Wash., a Navy statement said.

Some have speculated that the presence of three carrier groups in the Pacific is a direct response to North Korean aggression; however, Navy officials told Stars and Stripes Thursday the timing is just a coincidence.

“U.S. Navy Carrier Strike Groups routinely deploy to the Western Pacific and the Indian Ocean,” said 7th Fleet spokesman Lt. Paul Newell. “These deployments are part of a previously planned deployment cycle and it is not uncommon for incoming and outgoing carrier strike group transit timing to overlap as one begins a deployment the other concludes.”

The Nimitz’ sister carrier, the USS Theodore Roosevelt, arrived in the Pacific with its strike group on Monday. The group is on a regularly scheduled deployment to the Pacific and the Middle East, the Navy said.

The Roosevelt, also part of the Navy’s 3rd Fleet and homeported in San Diego, Calif., will likely take over missions previously conducted by the Nimitz.

“USS Theodore Roosevelt is prepared to carry out the full spectrum of possible missions, from humanitarian relief to combat operations,” the ship’s commander, Capt. Carlos Sardiello, said in a statement. “When a carrier leaves on deployment, we have to be ready for anything.”

Meanwhile, the 7th Fleet’s USS Ronald Reagan Strike Group stopped in Busan, South Korea, Saturday after a week of drills in nearby waters. The Yokosuka, Japan-based carrier’s port call comes at a time of heightened rhetoric between North Korea and Washington over the communist state’s missile tests and nuclear weapons program.